The present invention relates generally to temperature sensors suitable for sensing temperatures on the surface or within flexible insulations, and more specifically, to a temperature sensor having a two bore thin wall alumina tubing containing a type R (Platinum/Platinum/Rhodium) thermocouple wire. The sensor is bonded with alumina adhesive to the unexposed bottom surface of the top fabric of an insulation thus permitting the accurate detection of the surface temperature of the insulation.